Beam control assembly for ribbon beam of ions for ion implantation

ABSTRACT

A beam control assembly to shape a ribbon beam of ions for ion implantation includes a first bar, second bar, first coil of windings of electrical wire, second coil of windings of electrical wire, first electrical power supply, and second electrical power supply. The first coil is disposed on the first bar. The first coil is the only coil disposed on the first bar. The second bar is disposed opposite the first bar with a gap defined between the first and second bars. The ribbon beam travels between the gap. The second coil is disposed on the second bar. The second coil is the only coil disposed on the second bar. The first electrical power supply is connected to the first coil without being electrically connected to any other coil. The second electrical power supply is connected to the second coil without being electrically connected to any other coil.

CROSS REFERENCE TO RELATED APPLICATION

The present application claims priority to U.S. Provisional ApplicationSer. No. 60/919,365, filed Mar. 21, 2007, which is incorporated hereinby reference in its entirety.

BACKGROUND

1. Field

The present application generally relates to ion implanters, and, moreparticularly, to a beam control assembly to shape a ribbon beam of ionsfor ion implantation.

2. Related Art

Ion implanters are used to implant ions in various applications,including semiconductor device fabrication. As depicted in FIG. 1, anion implanter 100 typically includes an ion source 102 configured togenerate the ions, an accelerator 104 configured to accelerate the ionsto a desired energy, a beam control assembly 106 configured to shape theions into a desired pattern, and a target area 108 configured toposition the work piece, such as a wafer in semiconductor devicefabrication, for ion implantation.

To increase throughput, particularly in semiconductor applications, aribbon beam of ions is used. In particular, with reference to FIG. 2A, aribbon beam 202 can be generated and used to implant ion in an area of awork piece, such as a wafer in semiconductor applications. As depictedin FIG. 2A, ribbon beam 202 has a beam width 204 and travels in a beamdirection 206.

Various conventional devices and techniques exist for controlling ribbonbeam 202. For example, see, U.S. Pat. No. 7,078,713, issued Jul. 18,2006, and U.S. Pat. No. 6,933,607, issued Aug. 23, 2005, which areincorporated herein by reference in their entireties for all purposes.These conventional devices and techniques have various shortcomings inshaping a ribbon beam of ions for ion implantation.

SUMMARY

In one exemplary embodiment, a beam control assembly to shape a ribbonbeam of ions for ion implantation includes a first bar, second bar,first coil of windings of electrical wire, second coil of windings ofelectrical wire, first electrical power supply, and second electricalpower supply. The first coil is disposed on the first bar. The firstcoil is the only coil disposed on the first bar. The second bar isdisposed opposite the first bar with a gap defined between the first andsecond bars. The ribbon beam travels between the gap. The second coil isdisposed on the second bar. The second coil is the only coil disposed onthe second bar. The first electrical power supply is connected to thefirst coil without being electrically connected to any other coil. Thesecond electrical power supply is connected to the second coil withoutbeing electrically connected to any other coil.

DESCRIPTION OF DRAWING FIGURES

The present application can be best understood by reference to thefollowing description taken in conjunction with the accompanying drawingfigures, in which like parts may be referred to by like numerals:

FIG. 1 depicts an ion implanter;

FIG. 2A depicts a ribbon beam of ions;

FIGS. 2B and 2C depict an exemplary beam control assembly;

FIGS. 3A-3C depict another exemplary beam control assembly;

FIGS. 4-9 depict various exemplary beam control assemblies; and

FIG. 10 depicts an exemplary bar that can be used in an exemplary beamcontrol assembly.

DETAILED DESCRIPTION

The following description sets forth numerous specific configurations,parameters, and the like. It should be recognized, however, that suchdescription is not intended as a limitation on the scope of the presentinvention, but is instead provided as a description of exemplaryembodiments.

With reference to FIG. 2B, in one exemplary embodiment, a beam controlassembly 208 to shape a ribbon beam of ions for ion implantationincludes a first bar 210 and a second bar 212. Second bar 212 isdisposed opposite first bar 210 to define a gap 214 between second bar212 and first bar 210. The ribbon beam travels between gap 214.

As depicted in FIG. 2A, a first dimension 216 within beam controlassembly 208 corresponds to beam width 204. As also depicted in FIG. 2A,a second dimension 218 within beam control assembly 208 corresponds tobeam direction 206.

In one exemplary embodiment, first bar 210 is located at a firstposition 220 in second dimension 218 and extends into first dimension216. In this exemplary embodiment, as depicted in FIGS. 2B and 2C,second bar 212 is also located at first position 220 in second dimension218 and extends into first dimension 216. Alternatively, as depicted inFIG. 4, second bar 212 can be located at a second position 402 in seconddimension 218, which is different than first position 220.

With reference to FIG. 2A, beam control assembly 208 includes a firstcoil 222 disposed on first bar 210. In the present exemplary embodiment,first coil 222 is the only coil disposed on first bar 210. First coil222 includes windings of electrical wire. As depicted in FIG. 2C, thewindings of first coil 222 are concentric to first bar 210, whichcorresponds to being wound around first dimension 216 (FIG. 2A).

With reference again to FIG. 2B, beam control assembly 208 includes asecond coil 224 disposed on second bar 212. In the present exemplaryembodiment, second coil 224 is the only coil disposed on second bar 212.Second coil 224 includes windings of electrical wire. As depicted inFIG. 2C, the windings of second coil 224 are concentric to second bar212, which corresponds to being wound around first dimension 216 (FIG.2A).

With reference again to FIG. 2B, beam control assembly 208 includes afirst electrical power supply 226 electrically connected to first coil222 without being electrically connected to any other coil. Beam control208 also includes a second electrical power supply 228 electricallyconnected to second coil 224 without being electrically connected to anyother coil.

With reference to FIG. 2B, in one exemplary embodiment, first coil 222is fixed to first position 230 in first dimension 216 on first bar 210.In this exemplary embodiment, second coil 224 is also fixed to firstposition 230 in first dimension 216 on second bar 212. Second coil 224is located opposite first coil 222 at first position 230 in firstdimension 216. Thus, the portion of ribbon beam 202 adjacent to firstposition 230 in first dimension 216 can be controlled from both sides ofgap 214 using first coil 222 and first electrical power supply 226and/or second coil 224 and second electrical power supply 228.

With reference to FIG. 5, in another exemplary embodiment, second coil224 can be fixed to a second position 502 in first dimension 216 onsecond bar 212. In this exemplary embodiment, one portion of ribbon beam202 adjacent to first position 230 in first dimension 216 can becontrolled from one side of gap 214 using first coil 222 and firstelectrical power supply 226, and another portion of ribbon beam 202adjacent to second position 502 can be controlled from another side ofgap 214 using second coil 224 and second electrical power supply 228.

With reference to FIG. 2B, in another exemplary embodiment, first coil222 is configured to move along first bar 210 to be located at differentpositions in first dimension 216. Second coil 224 is configured to movealong second bar 212 to be located at different positions in firstdimension 216. Although not depicted, it should be recognized that firstcoil 222 and second coil 224 can be moved using various devices,including actuators, tracks, and the like.

With reference to FIG. 3B, in on exemplary embodiment, beam controlassembly 208 includes a third bar 302 and a fourth bar 304. Fourth bar304 is disposed opposite third bar 302 with gap 214 defined betweenfourth bar 304 and third bar 302. The ribbon beam travels between gap214.

As depicted in FIGS. 3A and 3C, third bar 302 is adjacent first bar 210.Third bar 302 is located at a third position 306 in second dimension 218and extends into first dimension 216. In one exemplary embodiment, asdepicted in FIGS. 3B and 3C, fourth bar 304 is located at third position306 in second dimension 218 and extends into first dimension 216.Alternatively, as depicted in FIG. 6, fourth bar 304 can be located atfourth position 602 in second dimension 218.

With reference to FIG. 3A, beam control assembly 208 also includes athird coil 308 disposed on third bar 302. In the present exemplaryembodiment, third coil 308 is the only coil disposed on third bar 302.Third coil 308 includes windings of electrical wire. As depicted in FIG.3C, the windings of third coil 308 are concentric to third bar 302,which corresponds to being wound around first dimension 216 (FIG. 3A).

Beam control assembly 208 includes a fourth coil 310 disposed on fourthbar 304. In the present exemplary embodiment, fourth coil 310 is theonly coil disposed on fourth bar 304. Fourth coil 310 includes windingsof electrical wire. The windings of fourth coil 310 are concentric tofourth bar 304, which corresponds to being wound around first dimension216 (FIG. 2A).

Beam control assembly 208 includes a third electrical power supply 312electrically connected to third coil 308 without being electricallyconnected to any other coil. Beam control 208 also includes a fourthelectrical power supply 314 electrically connected to fourth coil 310without being electrically connected to any other coil.

With reference to FIG. 3B, in one exemplary embodiment, third coil 308is fixed to a third position 316 in first dimension 216 on third bar302. In this exemplary embodiment, fourth coil 310 is also fixed tothird position 316 in first dimension 216 on fourth bar 304. Fourth coil310 is located opposite third coil 308 at third position 316 in firstdimension 216. Thus, the portion of ribbon beam 202 adjacent to thirdposition 316 in first dimension 216 can be controlled from both sides ofgap 214 using third coil 308 and third electrical power supply 312and/or fourth coil 310 and fourth electrical power supply 314.

With reference to FIG. 7, in another exemplary embodiment, fourth coil310 can be fixed to a fourth position 702 in first dimension 216 onfourth bar 304. In this exemplary embodiment, one portion of ribbon beam202 adjacent to third position 316 in first dimension 216 can becontrolled from one side of gap 214 using third coil 308 and thirdelectrical power supply 312, and another portion of ribbon beam 202adjacent to fourth position 702 can be controlled from another side ofgap 214 using fourth coil 310 and second electrical power supply 314.

With reference to FIG. 3B, in another exemplary embodiment, third coil308 is configured to move along third bar 302 to be located at differentpositions in first dimension 216. Fourth coil 310 is configured to movealong fourth bar 304 to be located at different positions in firstdimension 216. Although not depicted, it should be recognized that thirdcoil 308 and fourth coil 310 can be moved using various devices,including actuators, tracks, and the like.

In the exemplary embodiment depicted in FIG. 3A, first bar 210 and thirdbar 302 are depicted as extending in first dimension 216 across theentire beam width 204 of ribbon beam 202. As depicted in FIGS. 2B and3B, second bar 212 and fourth bar 304 also extend in first dimension 216across the entire beam width 204. Additionally, in this exemplaryembodiment, first bar 210, second bar 212, third bar 302, and fourth bar304 all extend from the same side of beam control assembly 208. Oneadvantage to this exemplary embodiment is that supply lines, includingelectrical lines, can be supplied from the same side.

With reference to FIG. 8, in another exemplary embodiment, first bar 210and third bar 302 extend in first dimension 216 across only a portion ofbeam width 204 of ribbon beam 202. Although not depicted, it should berecognized that second bar 212 and fourth bar 304 also extend in firstdimension 216 across only a portion of beam width 204 of ribbon beam202. As depicted in FIG. 8, in this exemplary embodiment, first bar 210and third bar 302 can extend from opposite sides of beam controlassembly 208. Similarly, second bar 212 and fourth bar 304 can alsoextend from opposite sides of beam control assembly 208.

With reference to FIGS. 3A and 8, when first coil 222 and third coil 308are fixed to first position 230 and third position 316, respectively, onfirst bar 210 and third bar 302, respectively, first coil 222 and thirdcoil 308 can be positioned such that the portion of ribbon beam 202adjacent to first coil 222 overlaps with the portion of ribbon beam 202adjacent to third coil 308. In a similar manner, second coil 224 andfourth coil 310 can be positioned such that the portion of ribbon beam202 adjacent to second coil 224 overlaps with the portion of ribbon beam202 adjacent to fourth coil 310.

It should be recognized that beam control assembly 208 can include anynumber of bars located at different positions along second dimension218, each bar having only one coil disposed on the bar, with the coilsof the different bars located at different positions along firstdimension 216. For example, FIG. 9 depicts 8 bars located at 8 differentpositions along second dimension 218, each bar having only one coildisposed on the bar, with the 8 coils of the 8 different bars located at8 different positions along first dimension 216 such that the entirebeam width 204 of ribbon beam 202 can be controlled separately by thecoils.

With reference to FIG. 10, in one exemplary embodiment, the barsdescribed above (such as first bar 210 in FIG. 2) are steel bars. Asdepicted in FIG. 10, the bars can have a greatest width 1002 of about 50to 100 mm. It should be recognized, however, that the bars can be madeof various types of materials, and have various dimensions.

Also, the coils described above (such as first coil 222 in FIG. 2A) weredescribed as being windings of electrical wire. In one exemplaryembodiment, the coils are copper wires. It should be recognized,however, that the coils can be made of various types of electricallyconductive material.

Although exemplary embodiments have been described, variousmodifications can be made without departing from the spirit and/or scopeof the present invention. Therefore, the present invention should not beconstrued as being limited to the specific forms shown in the drawingsand described above.

1. A beam control assembly to shape a ribbon beam of ions for ionimplantation, the beam control assembly comprising: a first bar; a firstcoil disposed on the first bar, wherein the first coil is the only coildisposed on the first bar, and wherein the first coil includes windingsof electrical wire; a second bar disposed opposite the first bar with agap defined between the first bar and second bar, wherein the ribbonbeam travels between the gap; a second coil disposed on the second bar,wherein the second coil is the only coil disposed on the second bar, andwherein the second coil includes windings of electrical wire; a firstelectrical power supply connected to the first coil without beingelectrically connected to any other coil; and a second electrical powersupply connected to the second coil without being electrically connectedto any other coil.
 2. The beam control assembly of claim 1, wherein theribbon beam has a beam width and travels in a beam direction, wherein afirst dimension corresponds to the beam width and a second dimensioncorresponds to the beam direction of the ribbon beam, wherein the firstbar is located at a first position in the second dimension and extendsinto the first dimension, wherein the second bar is located at the firstposition in the second dimension and extends into the first dimension.3. The beam control assembly of claim 1, wherein the ribbon beam has abeam width and travels in a beam direction, wherein a first dimensioncorresponds to the beam width and a second dimension corresponds to thebeam direction of the ribbon beam, wherein the first bar is located at afirst position in the second dimension and extends into the firstdimension, wherein the second bar is located at a second position in thesecond dimension and extends into the first dimension, and wherein thefirst and second positions are different.
 4. The beam control assemblyof claim 1, wherein the ribbon beam has a beam width and travels in abeam direction, wherein a first dimension corresponds to the beam widthand a second dimension corresponds to the beam direction of the ribbonbeam, wherein the first coil is configured to move along the first barto be located at different positions in the first dimension on the firstbar, and wherein the second coil is configured to move along the secondbar to be located at different positions in the first dimension on thesecond bar.
 5. The beam control assembly of claim 1, wherein the ribbonbeam has a beam width and travels in a beam direction, wherein a firstdimension corresponds to the beam width and a second dimensioncorresponds to the beam direction of the ribbon beam, wherein the firstcoil is fixed to a first position in the first dimension on the firstbar, and wherein the second coil is fixed to the first position in thefirst dimension on the second bar.
 6. The beam control assembly of claim1, wherein the ribbon beam has a beam width and travels in a beamdirection, wherein a first dimension corresponds to the beam width and asecond dimension corresponds to the beam direction of the ribbon beam,wherein the first coil is fixed to a first position in the firstdimension on the first bar, and wherein the second coil is fixed to asecond position in the first dimension on the second bar, and whereinthe first and second positions are different.
 7. The beam controlassembly of claim 1, further comprising: a third bar adjacent to thefirst bar; a third coil disposed on the third bar, wherein the thirdcoil is the only coil disposed on the third bar, wherein the third coilincludes windings of electrical wire; a fourth bar adjacent to thesecond bar; a fourth coil disposed on the fourth bar, wherein the fourthcoil is the only coil disposed on the fourth bar, wherein the fourthcoil includes windings of electrical wire; a third electrical powersupply connected to the third coil without being electrically connectedto any other coil; and a fourth electrical power supply connected to thefourth coil without being electrically connected to any other coil. 8.The beam control assembly of claim 7, wherein the ribbon beam has a beamwidth and travels in a beam direction, wherein a first dimensioncorresponds to the beam width and a second dimension corresponds to thebeam direction of the ribbon beam, wherein the third bar is located at athird position in the second dimension and extends into the firstdimension, wherein the fourth bar is located at the third position inthe second dimension and extends into the first dimension.
 9. The beamcontrol assembly of claim 7, wherein the ribbon beam has a beam widthand travels in a beam direction, wherein a first dimension correspondsto the beam width and a second dimension corresponds to the beamdirection of the ribbon beam, wherein the third bar is located at athird position in the second dimension and extends into the firstdimension, wherein the fourth bar is located at a fourth position in thesecond dimension and extends into the first dimension, and wherein thethird and fourth positions are different.
 10. The beam control assemblyof claim 7, wherein the ribbon beam has a beam width and travels in abeam direction, wherein a first dimension corresponds to the beam widthand a second dimension corresponds to the beam direction of the ribbonbeam, wherein the third coil is configured to move along the third barto be located at different positions in the first dimension on the thirdbar, and wherein the fourth coil is configured to move along the fourthbar to be located at different positions in the first dimension on thefourth bar.
 11. The beam control assembly of claim 7, wherein the ribbonbeam has a beam width and travels in a beam direction, wherein a firstdimension corresponds to the beam width and a second dimensioncorresponds to the beam direction of the ribbon beam, wherein the thirdcoil is fixed to a third position in the first dimension on the thirdbar, and wherein the fourth coil is fixed to the third position in thefirst dimension on the fourth bar.
 12. The beam control assembly ofclaim 7, wherein the ribbon beam has a beam width and travels in a beamdirection, wherein a first dimension corresponds to the beam width and asecond dimension corresponds to the beam direction of the ribbon beam,wherein the third coil is fixed to a third position in the firstdimension on the third bar, and wherein the fourth coil is fixed to afourth position in the first dimension on the fourth bar, and whereinthe third and fourth positions are different.
 13. The beam controlassembly of claim 7, wherein the first, second, third, and fourth barsextend in the first dimension across the entire beam width.
 14. The beamcontrol assembly of claim 13, wherein the first, second, third andfourth bars extend from one side of the beam control assembly.
 15. Thebeam control assembly of claim 7, wherein the first, second, third, andfourth bars extend in the first dimension across a portion of the beamwidth.
 16. The beam control assembly of claim 15, wherein the first andsecond bars extend from one side of the beam control assembly, andwherein the third and fourth bars extend from an opposite side of thebeam control assembly as the first and second bars.
 17. The beam controlassembly of claim 7, wherein a portion of the ribbon beam adjacent tothe first coil overlaps with a portion of the ribbon beam adjacent tothe third coil.
 18. An ion implanter to implant ions using a ribbon beamof ions, comprising: an ion source; an accelerator configured toaccelerate the ion disposed adjacent to the ion source; a beam controlassembly disposed adjacent to the accelerator, the beam control assemblycomprising: a first bar; a first coil disposed on the first bar, whereinthe first coil is the only coil disposed on the first bar, and whereinthe first coil includes windings of electrical wire; a second bardisposed opposite the first bar with a gap defined between the first barand second bar, wherein the ribbon beam travels between the gap; asecond coil disposed on the second bar, wherein the second coil is theonly coil disposed on the second bar, and wherein the second coilincludes windings of electrical wire; a first electrical power supplyconnected to the first coil without being electrically connected to anyother coil; and a second electrical power supply connected to the secondcoil without being electrically connected to any other coil; and atarget area disposed adjacent to the beam control assembly, the targetarea configured to position a work piece.
 19. The ion implanter of claim18, wherein the beam control assembly further comprises: a third baradjacent to the first bar; a third coil disposed on the third bar,wherein the third coil is the only coil disposed on the third bar,wherein the third coil includes windings of electrical wire; a fourthbar adjacent to the second bar; a fourth coil disposed on the fourthbar, wherein the fourth coil is the only coil disposed on the fourthbar, wherein the fourth coil includes windings of electrical wire; athird electrical power supply connected to the third coil without beingelectrically connected to any other coil; and a fourth electrical powersupply connected to the fourth coil without being electrically connectedto any other coil.
 20. A method of controlling a ribbon beam of ions,the method comprising: applying an electrical charge to a first coilusing a first electrical power supply, wherein the first electricalpower supply is connected to the first coil without being electricallyconnected to any other coil, wherein the first coil is disposed on afirst bar, wherein the first coil is the only coil disposed on the firstbar, and wherein the first coil includes windings of electrical wire;and applying an electrical charge to a second coil using a secondelectrical power supply, wherein the second electrical power supply isconnected to the second coil without being electrically connected toanother other coil, wherein the second coil is disposed on a second bar,wherein the second coil is the only coil disposed on the second bar,wherein the second coil includes windings of electrical wire, whereinthe second bar is disposed opposite the first bar with a gap definedbetween the first bar and second bar, and wherein the ribbon beamtravels between the gap.